A dialect or informal term for gypsum or clay mixed with other materials, sometimes used in construction or plasterwork.
Of uncertain origin, possibly from Turkish gatch or a similar word. The term appears in regional British English and construction terminology, suggesting a loan word from Near Eastern languages.
Gatch appears in historical construction documents with wildly different meanings—sometimes it's the main plaster ingredient, sometimes a filler—showing how specialized trades develop their own jargon that outsiders completely misunderstand.
Complete word intelligence in one call. Free tier — 50 lookups/day.